Carton blank



FIG. 1 is a top plan view of a carton blank embodying my new design, the bottom being a mirror image thereof;

FIG. 2 is a front elevational view;

FIG. 3 is a side elevational view;

FIG. 4 is a rear elevational view; and

FIG. 5 is a side elevational view showing the side opposite that seen in FIG. 2. 

The ornamental design for a carton blank, as shown and described. 